Primer for cannon



(ModeL) J. B. RODMAN.

Primer for Cannon.

No. 232,210; Patented Sept. 14, i880.'

' WITNESSES: INVENTOR:

' TORNEYS.

UNITED STATES PATENT FFICE.

JOHN B. RODMAN, OF FORT BROWN, TEXAS.

PRIMER FOR CANNON.

SPECIFICATION forming part of Letters Patent No. 232,210, dated September 14, 1880.

Application filed July 16, 1880.

To all whom it may concern:

Be it known that I, JOHN'B. RODMAN, of Fort Brown, in the county of Cameron and State of Tex-as, have invented a new and useful Improvement in Primers for Cannon, of which the following is a specification.

Friction and percussion tubes have heretofore been made for insertion in the vent-holes of cannon to fire the same; but, as well known, the vent becomes enlarged by use, so that the tubes fit loosely, and either blow out without igniting the charge in the cannon, or else the tubes break off below the firing-wire, on account of not being solidly held.

The object of my invention is to provide for holding priming-tubes securely, and thus insure their proper operation; and in yinvention consists in a spring combined with the priming-tube, which spring expands to the size of the vent and holds the tube with the, necessary amount of friction against the walls of the vent. 4 In the accompanying drawings, forming part of this specification, Figure 1 is a longitudinal section of the breech portion of a cannon with my improved priming-tube applied in the vent. Fig. 2 is a perspective View of theprimer.

Similar letters of reference indicate corresponding parts.

A is the tube of the, primer, provided with the friction-wire a,'as usual; and b is the spring attached to the'tube, which spring constitutes my improvement.

(Model) The spring I) is made of suitable material, 3

and attached to the lower end of the tube by brazing, riveting, or other suitable means; or the spring may be a prolongation of the tube bent back to the desired position.

The spring may be of a shape for fitting 4o snugly to the tube when pressed thereon, so as not to materially increase the size of the tube, and also to fit the walls of the vent closely. The outer surface of the spring will preferably be roughened to insure greater trio-" 5 tion.

It will be seen that when the tube A is inserted in the vent ot' the cannon, as usual, the spring b will insure a tight fit, so that the tube is solidly held, and with sufficient fric- 50 with the tube A, that carries the friction-wire, 60

substantially as and for the purpose specified.

JOHN BLACK RODMAN.

Witnesses:

JAMES A. BROWNE, LOUIS KOWALSKI. 

